1. Field of the Invention
The present invention relates to the devices and methods for controlling the excretion of waste from the human body, and more particularly, to a device and method for selectively controlling defecation in colostomy patients due to colorectal cancer, disease, injury, birth defect, or other causes.
2. Background of the Related Art
The rectum with sphincter musculature provides the collection point and discharge mechanism for waste elimination. Cancers of the colon and rectum are two of the most common cancers in the United States. Together, they are referred to as colorectal cancer.
Surgical removal of a malignant tumor is the most common treatment for colorectal cancer. The diseased portion of the colon, rectum and/or anus is removed, and in most cases, the healthy portions are reattached. However, approximately 5% of patients with colorectal cancer require a colostomy because of the extent of the disease or its location. In such cases, a surgical opening is made through the abdomen to provide a new path for waste elimination, whereby the patient is required to excrete through a stoma (small aperture in the skin) and into a colostomy bag. Since the colostomy bag can only be used for liquid feces, the surgeon also removes the large intestine, even though a majority of it might be healthy, in order to prevent the formation of any solid feces and thereby ensure the proper passage of the feces through the stoma and into the colostomy bag.
A colostomy also may be performed to treat traumatic injuries to the bowel, diverticulitis, and inflammatory bowel disease, when other treatment measures fail. Currently, there is a population of about 850,000 people in North America that live with the condition, with about 7,000 new cases of colostomy due to colorectal cancer reported annually based on Cleveland Clinic statistics. Worldwide, U.N. statistics estimate 3.5 million patients in developed countries alone live with colostomy.
Several devices have been developed to allow such patients limited control over their need to eliminate wastes from their bodies. For example, U.S. Patent Application No. 2001/00223337 A1 to Lapcevic shows an apparatus that evacuates human waste products from a stoma which includes a battery-powered or manual evacuator pump activated by an external switch or operator to empty the shortened bowel. The evacuator assembly is adapted to seal over the stoma during operation, after which it may be removed.
Further examples include U.S. Pat. No. 4,351,322 to Prager which shows a stoma control device having a ring for surgical implantation around an emerging bowel. A plug is adapted to fit within the distal end of the bowel which selectively inflates to engage the surrounding tissue and ring to block the stoma.
Still further, U.S. Pat. No. 4,217,899 to Freir shows a prosthesis permanently attached to the distal end of the intestinal tract that allows waste products to accumulate. Elimination of the waste products is through a removable assembly of an elastic liner and support structure that communicates with the affixed portion of the prosthesis to collect the waste.
In light of the foregoing, a need exists for an artificial rectum which provides selective control over the excretion of fecal matter to obviate the need for removal of the large intestine in a patient and the associated use of a stoma for collection/removal of waste products.